ATLAS/ICESat-2 L2A Global Geolocated Photon Data, Version 7
Data set id:
ATL03
DOI: 10.5067/ATLAS/ATL03.007
This is the most recent version of these data.
Version Summary
Version Summary
-ATL02 improved TOF, range calibrations, and range bias correction (average change in range is about -0.7 mm).
-ATL02 added a variable to the first photon bias and radiometric correction tables to reflect invalid correction values due to unreliable calibration values. New variable max_valid_stren_strong carried from ATL02 for rad_corr (CAL19) and ffb_corr (CAL34).
-Moved from ITRF2014 to ITRF2020. Up to a 7 mm regional height change, maximum values at poles.
-ANC03/04 products generated from POD solutions use updated global modeling.
-Correction to the center-of-mass data set generation in ANC04, which should shift the z-component by ~1.0–1.2 cm during airplane mode periods (solar array, i.e., SADA). Airplane/sailboat changes are documented in the Major Activities Table, under the yaw flip changes.
-ANC05 products were calibrated using results from recent full mission week calibration solutions.
-Used GEOS5-IT for atmosphere delay calculation from NASA GMAO. No significant height change from v6 based on ~1 month of photon-to-photon comparisons
-Updated tide model from GOT4.8 to an extrapolated FES2014b for ocean, load and long-period tides. FES2014b has a higher spatial resolution, improved predictions, and improved near-shore coverage. Land masks are not applied to the tide parameters on ATL03. No adverse systemic change in affected parameters between v6 and v7. Parameters affected in /gtx/geophys_corr include tide_ocean, tide_load, and tide_equilibrium.
-Updated weight_ph to use DDA-03’s Radial Basis Function Normalized for Instrument Characteristics. This allows weight_ph values to be consistent across all ICESat-2 data, as opposed to v6 where weight_ph values were normalized within a geosegment.
-Added signal_class_ph as experimental DDA-03 parameter to classify photons using algorithms developed for evaluating weight_ph.
-Updated quality_ph to include flag values to identify noise bursts and streaks, and all photons in a pulse that are considered nearly or fully saturated and whether the return occurs at the surface, after pulse, impulse response. v6 flag values of 1 and 2 are obsolete in v7.
-Added beta_angle and orbit_angle at geoseg rate, carried forward from ATL03g.
-Cloud optimization of H5 files for more efficient access/use in cloud environments.
-Product metadata updates.
-ATL02 added a variable to the first photon bias and radiometric correction tables to reflect invalid correction values due to unreliable calibration values. New variable max_valid_stren_strong carried from ATL02 for rad_corr (CAL19) and ffb_corr (CAL34).
-Moved from ITRF2014 to ITRF2020. Up to a 7 mm regional height change, maximum values at poles.
-ANC03/04 products generated from POD solutions use updated global modeling.
-Correction to the center-of-mass data set generation in ANC04, which should shift the z-component by ~1.0–1.2 cm during airplane mode periods (solar array, i.e., SADA). Airplane/sailboat changes are documented in the Major Activities Table, under the yaw flip changes.
-ANC05 products were calibrated using results from recent full mission week calibration solutions.
-Used GEOS5-IT for atmosphere delay calculation from NASA GMAO. No significant height change from v6 based on ~1 month of photon-to-photon comparisons
-Updated tide model from GOT4.8 to an extrapolated FES2014b for ocean, load and long-period tides. FES2014b has a higher spatial resolution, improved predictions, and improved near-shore coverage. Land masks are not applied to the tide parameters on ATL03. No adverse systemic change in affected parameters between v6 and v7. Parameters affected in /gtx/geophys_corr include tide_ocean, tide_load, and tide_equilibrium.
-Updated weight_ph to use DDA-03’s Radial Basis Function Normalized for Instrument Characteristics. This allows weight_ph values to be consistent across all ICESat-2 data, as opposed to v6 where weight_ph values were normalized within a geosegment.
-Added signal_class_ph as experimental DDA-03 parameter to classify photons using algorithms developed for evaluating weight_ph.
-Updated quality_ph to include flag values to identify noise bursts and streaks, and all photons in a pulse that are considered nearly or fully saturated and whether the return occurs at the surface, after pulse, impulse response. v6 flag values of 1 and 2 are obsolete in v7.
-Added beta_angle and orbit_angle at geoseg rate, carried forward from ATL03g.
-Cloud optimization of H5 files for more efficient access/use in cloud environments.
-Product metadata updates.
Overview
ATL03 contains height above the WGS 84 ellipsoid, latitude, longitude, and time for each photon downlinked by the Advanced Topographic Laser Altimeter System (ATLAS) instrument on board ICESat-2. This product was designed to be a single source for all photon data and ancillary information needed by higher-level ATLAS/ICESat-2 products.
Parameter(s):
TERRAIN ELEVATION
Platform(s):
ICESat-2
Sensor(s):
ATLAS
Data Format(s):
HDF5
Temporal Coverage:
- 13 October 2018 to present
Temporal Resolution:
- 91 day
Spatial Resolution:
- 0.7 m
- 0.7 m
Spatial Reference System(s):
- WGS 84EPSG:4326
Spatial Coverage:
- N:88S:-88E:180W:-180
Blue outlined yellow areas on the map below indicate the spatial coverage for this data set.
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